Looking ahead to this winter! Will It Be a Cold One?
ContactRelief Consulting Meteorologist Dr. Kevin Levey looks at the long-range temperature forecast for the upcoming winter season.
Tuesday, 10 October 2017 08:00:00 -05:00
But First...Hurricane Season Is Not Over
As I said in a prior post, hurricane season is not over. Last week, another hurricane made landfall in the United States. Hurricane Nate formed in the Caribbean and intensified into a category 1 hurricane with sustained winds of 85 mph and made landfall in the Biloxi area of Mississippi. Fortunately for the Gulf Coast region, the damage was limited.
Elsewhere, Tropical Storm Ophelia formed in the Atlantic but was never forecasted to threaten the United States. The storm is expected to become a hurricane today or tomorrow and move to the east-northeast towards the European coastline.
Expected Winter Weather Outlook
Continuing from last week with my discussion on the expected winter outlook, I will discuss the NMME monthly temperature outlooks. As a recap, there are a number of climate models that try to predict the temperature and precipitation on a monthly basis for at least six months into the future. The North American Multi-Model Ensemble (NMME) is an experimental multi-model seasonal forecasting system consisting of coupled models from US modeling centers including NOAA/NCEP, NOAA/GFDL, IRI, NCAR, NASA, and Canada's CMC. Instead of just using one single model, the NMME is preferred since it is a combination of many climate models and yields better forecasts than any one single individual model. The following maps show the expected monthly average temperature departures.
Figure 2 above shows that for October 2017, almost the entire country should expect above-average temperatures, with the vast majority of the western, northern tier states and northern Alaska with forecast departures of +1-2?C and the smallest positive departures over the east coast and Northeast. The southeast coast and most of Florida should expect mostly average temperatures.
Figure 3 above, shows that with the exception of Florida, November 2017 temperatures are forecast to be above average with positive departures of +0.5-1?C, but +1-2?C over most of Wisconsin, both Dakotas and northern Alaska.
Figure 4 above, shows that December 2017 temperatures will be above average over much of most of Alaska, the Central Plains and the eastern half of the country with departures of +1-2?C. The Pacific Northwest is expected to have mostly average temperatures and California, Nevada, Idaho and Montana should expect slightly above average temperatures of +0.25-0.5?C.
Figure 5 above, shows continued above average temperatures over the eastern third of the country with departures of +1-2?C, but less so over the Central Plains and Midwest with departures of +0.25-1?C. Below average temperatures are forecast over the Pacific Northwest, Idaho and most of western Montana and far northern California with departures of -0.25-1?C. Elsewhere, average temperatures are forecast.
Figure 6 above, shows that during February 2018, forecast temperatures are expected to be above average over almost the entire country, with the exception of most of Washington and Oregon. Much of the country will experience positive departures of +1-2?C, but slightly less over the northern tier states, Nevada, Utah and Wyoming with departures mostly between +0.25-1?C
Finally, Figure 7 above, shows that March 2018 will be very similar to those forecast for February 2018. Forecast temperatures are expected to be above average over almost the entire country, with the exception of most of Washington. Much of the country will experience positive departures of +1-2?C, but slightly less over the northern tier states, Nevada, Utah and Wyoming with departures mostly between +0.25-1?C. Oregon and most of California, Idaho and western Montana should expect mostly average temperatures.